Levallois technology is often considered one of many hallmarks of the Middle Palaeolithic (MP) and Middle Stone Age (MSA), although it is not always present (McBrearty and Tryon, 2006; White et al., 2011; Kuhn, 2013; Malinsky-Buller, 2016). As such, the development of this core volume shaping technology is at the center of debates regarding the transition from the Lower Palaeolithic (LP) and Early Stone Age (ESA) to the MP and MSA in different regions. A central question within this debate is whether Levallois originated solely on the African continent and dispersed into Eurasia with expanding populations (e.g., Foley and Lahr, 1997) or if different populations converged on the same technology in different regions at different times (e.g., Rolland, 1995; Adler et al., 2014). Research surrounding the origins of Levallois technology has increased over the last two decades, with a growing number of studies supporting a multiple-origin model (McBrearty et al., 1996; Kuman, 2001; White et al., 2011; Fontana et al., 2013; Picin et al., 2013, Picin, 2018; Adler et al., 2014; Chazan, 2016; Shimelmitz et al., 2016; Akhilesh et al., 2018; Gill et al., 2021; Rosenberg-Yefet et al., 2021, 2022; Shemer et al., 2022). Within this model, different hypotheses have been proposed to explain how Levallois technology evolved from preceding Acheulian technocomplexes. These include scenarios in which Levallois technology is the outcome of core elaboration (White and Ashton, 2003; McBrearty and Tryon, 2006; Kuman, 2001; White et al., 2011) or bifacial large cutting tool (LCT; sensu Lotter et al., 2022) evolution in the Late Acheulian (Rolland, 1995; Fontana et al., 2013; Chazan, 2016). Regardless of the evolutionary process leading to Levallois technology, it is likely adopted as a means of exerting greater control over the size and shape of flakes (Boëda, 1995; Schlanger, 1996; Muller and Clarkson, 2022) and is related to the shift toward more mobile tool kits (White and Pettitt, 1995; Brantingham and Kuhn, 2001; Eren and Lycett, 2012) and the proliferation of hafted tools (Barham, 2013; Rots, 2013; Degano et al., 2019; Niekus et al., 2019) in the MP and MSA.

Here we examine and compare Levallois technology and its relationship with other production systems in some of the regions with proposed Late Acheulian-Early Levallois (hereafter Acheul-Lev) transitional evidence. Sites in Britain and the Armenian Highlands were chosen for this study as the proposed evidence for a local transition is roughly contemporaneous, but the geographic distance and general environmental differences minimize the likelihood that the populations and development/introduction of Levallois technology are directly related. Furthermore, the chronology of the sites included in our study allow for introduction and innovation as equally plausible hypotheses for the appearance of Levallois technology. We employ landmark-based geometric morphometrics (GM) to three-dimensional (3D) scans of lithic artifacts from sites in these regions dating to Marine Isotope Stages (MIS) 11–9, when prepared core technology developed. Middle Palaeolithic sites dating to 8–7 are also included to better contextualize Levallois technology. Geometric morphometrics analysis is used in conjunction with measures of reduction intensity and size, and data on raw material sourcing are used to address morphology imposed through decision-making. Our results support a scenario in which Levallois prepared core technology is the outcome of different evolutionary processes in the Armenian Highlands and Britain.